Blac Chyna‘s most recent sex tape partner is her ex-boyfriend, Mechie … according to him, and even though he admits recording it himself, he’s as pissed as she is about the leak.

A rep for Mechie tells TMZ … the explicit video showing a naked Chyna performing oral sexwas shot back in July. We’re told Mechie was the one who recorded the encounter, but it was all captured using Chyna’s phone.

His rep says Mechie never had his own copy of the video, so he has no clue how it got out